How Do I Move The Center Of My Model To The Blender Origin?
I'm not sure there is an easy way.  The hard way that I can think of is to use the 3d cursor to move the origin of the object, move the cursor back to (0,0,0) and move the object to the cursor.  Unfortunately you then have to move the object origin back where it belongs.

The origin of an object starts out as the geometric center of the object.  It appears as a small yellow dot. Step by step to do this


select the object in object mode
switch to edit mode (TAB-KEY)
switch to face select mode (CTRL-TAB and select face mode from the pop up)
move the 3d cursor to the center of the face (SHIFT-S and select cursor to selection)
switch to object mode (TAB-KEY)
Move the origin of the object to the cursor (SHIFT-CTRL-ALT-C and select origin to 3d cursor)
Move the cursor to the origin (SHIFT-S and select Cursor to center)
Move the object to the cursor (SHIFT-S and select Selection to cursor)
Set the origin back to the geometry (SHIFT-CTRL-ALT-C and select origin to geometry)


There are other ways, but this one introduces you to using the cursor to precisely align objects.